D1- Most children aged 4 years old like to interact with other children their age, they also like sharing and taking turns playing with a certain toy sometimes the children prefer to play by themselves or playing with an imaginary friend. Children like to feel the security from parents and seek their approval when playing a game they love to have social interaction with other children but when they are playing with other children they like to play dress up and/or role play. http://www.nncc.org/child.dev/ages.stages.4y.html
Children aged 4 years old can go to the toilet sometimes supervised, they can chose their own clothes and get dressed by themselves. They sometimes try and help make their own lunch e.g. spreading the butter and adding the filling, also a four year old are capable of holding a knife or a fork just like holding a pencil this will improve their handwriting.
D2- Most children aged 5 years old are cheerful, energetic and they enjoy planning games, children aged 5 years old can get confused fantasy with the real world, they can share and take turns with toys but might not always want to. Children like to try new things and takes risks. When children play games with other children they like to be in groups of 1 or 2 and even then they can become bossy or sulky when others join in. http://www.nncc.org/child.dev/ages.stages.5y.html
Children aged 5 years old will have the strength to undo zips on coats, jackets or shoes they will be able to get dressed quicker. At this age they will want to bath themselves but they will need supervision. You should allow your child to pour their own milk in to their breakfast or cup.
D3- When observing children the best method to do so is narrative observation because it is a detailed account of everything that you see that particular child doing. You need to choose a suitable activity where you can see the child doing what you are looking for. Social skills are very important...