My 3 years old baby boy weight 3.20kg is it normal. But due to seasonal he loses his weight to 2.75kg is it normal

A. Madam your child is three years old or three months old that’s not looking like a child who is three months over if your child is losing on to its weight so it’s better to check with your doctor because due to seasonal issue the way does not go down I need to have a word with your doctor about it