Among the options provided, an 8-week-old full-term infant with normal developmental milestones will smile in response to appropriate stimuli.Rationale:Smiles in response to appropriate stimuli are seen from around 6 weeks of age. A social smile, where the infant has an awareness that a smile attracts attention, is not observed until around 3 months of age.Other options:- At 6 weeks an infant is able to follow objects in the horizontal plane through 90 deg| fixing and following an object through 180 deg in the horizontal plane is a milestone achieved at 3 months, as is pushing up onto forearms. – Pushing up onto hands occurs by around 5 months.- Infants of 3 months should startle to a 60 dB sound.

6 month old milestones:Social and Emotional:Knows familiar faces and begins to know if someone is a stranger Likes to play with others, especially parents Responds to other people’s emotions and often seems happy Likes to look at self in a mirror Language/Communication:Responds to sounds by making sounds Strings vowels together when babbling (“ah,” “eh,” “oh”) and likes taking turns with parent while making sounds Responds to own name Makes sounds to show joy and displeasure Begins to say consonant sounds (jabbering with “m,” “b”) Cognitive (learning, thinking, problem-solving):Looks around at things nearby Brings things to mouth Shows curiosity about things and tries to get things that are out of reach Begins to pass things from one hand to the other Movement/Physical Development:Rolls over in both directions (front to back, back to front) Begins to sit without support When standing, supports weight on legs and might bounce Rocks back and forth, sometimes crawling backwards before moving forward

Based on the presentation, the developmental age of the child is 8 months.The primitive reflexes are indicators of functional integrity and maturity. The majority of reflexes do not persist beyond 6 months of age. There are 13 reflexes of importance, including:- Moro reflex- Startle reflex- Rooting reflex- Sucking reflex- Grasp reflex- Voluntary palmar grasp reflex- Voluntary reach reflex- Stepping reflex- Asymmetrical tonic neck reflex (ATNR)- Parachute reflex- Plantar reflex- Tendon reflex- ClonusIt is interesting to note that gastrocolic reflex is not a primitive reflex.Ninety-five per cent of reflexes will have disappeared by the ages shown below:- 6 weeks: Stepping- 3-4 months: Palmar grasp and Moro- 6 months: Sucking, rooting, and asymmetrical tonic neck reflex (ATNR)

A three-year child’s typical developmental milestones include walking up and down the stairs with alternating feet, jumping in a place with two feet together, and jumping forward for about 2 feet. The child can pedal a tricycle and can throw a ball over and underhand. An average child should start walking around 12-14 months of age and should be investigated as early as 18 months if they do not begin to walk. Skipping can be done by a child of 5 years of age. A child of 6-7 years of age can ride a bike with stabilizers and can balance on one foot for 20 seconds.

Not being able to form a sentence at the age of 18 months is quite normal. A combination of two words to form a sentence can be done by 2 years of age.

At the age of 18 months, Gertrude should be able to follow a one step command. At this age she would also be capable of putting words together in 1 or 2 word phrases, scribbling, throwing a ball, and building a tower of four cubes. At 2 she should be able to feed herself with a spoon or a fork, copy a vertical line, ride a tricycle, kick a ball and balance on one foot. Activities such as jumping will follow later on in her development at 3 years.

Among the options provided, a 1-year-old child will be able to understand object permanence e.g. understands that objects continue to exist even when they can’t be seen, e.g. looking for a fallen toy.At the age of 1 year, children should have developed an accurate pincer grip and be able to see and co-ordinate and manipulate fairly small objects such as a raisin.Gross motor development varies, but the average 1-year-old should be able to stand and cruise around furniture or walk with their hands held but not necessarily walk unaided.Drinking from a cup will become established at around 15 months and scribbling at 18 months.

All the given development milestones are compatible with the given age.

3-year-old milestones:Social and Emotional:- Copies adults and friends – Shows affection for friends without prompting – Takes turns in games – Shows concern for crying friend – Understands the idea of “mine” and “his” or “hers” – Shows a wide range of emotions – Separates easily from mom and dad – May get upset with major changes in routine- Dresses and undresses self Language/Communication- Follows instructions with 2 or 3 steps – Can name most familiar things – Understands words like “in,” “on,” and “under” – Says first name, age, and sex- Names a friend – Says words like “I,” “me,” “we,” and “you” and some plurals (cars, dogs, cats) – Talks well enough for strangers to understand most of the time – Carries on a conversation using 2 to 3 sentencesCognitive (learning, thinking, problem-solving)- Can work toys with buttons, levers, and moving parts – Plays make-believe with dolls, animals, and people – Does puzzles with 3 or 4 pieces – Understands what “two” means – Copies a circle with a pencil or crayon – Turns book pages one at a time – Builds towers of more than 6 blocks – Screws and unscrews jar lids or turns the door handleMovement/Physical Development- Climbs well – Runs easily – Pedals a tricycle (3-wheel bike) – Walks up and downstairs, one foot on each stepDoing up buttons is a skill more usually seen in 5-year-olds.

Milestones of 12-month-old child are as follows:Social and Emotional- Is shy or nervous with strangers- Cries when mom or dad leaves- Has favourite things and people camera- Shows fear in some situations- Hands you a book when he wants to hear a story- Repeats sounds or actions to get attention- Puts out arm or leg to help with dressing – Plays games such as “peek-a-boo” and “pat-a-cake” Language/Communication- Responds to simple spoken requests- Uses simple gestures, like shaking head “no” or waving “bye-bye”- Makes sounds with changes in tone (sounds more like speech)- Says “mama” and “dada” and exclamations like “uh-oh!”- Tries to say words you sayCognitive (learning, thinking, problem-solving)- Explores things in different ways, like shaking, banging, throwing- Finds hidden things easily- Looks at the right picture or thing when it’s named- Copies gestures- Starts to use things correctly| for example, drinks from a cup, brushes hair- Bangs two things together- Puts things in a container, takes things out of a container- Lets things go without help- Pokes with index (pointer) finger – Follows simple directions like “pick up the toy”Movement/Physical Development- Gets to a sitting position without help – Pulls up to stand, walks holding on to furniture (“cruising”)- May take a few steps without holding on- May stand alone