Down syndrome affects each child differently, depending on the type of chromosomal abnormality they have inherited. There are usually distinguishing physical aspects present, such as a small skull, lack of a nose bridge, bulbous eyes, muscular hypotonia, hyper-flexible joints and tendons, shortened fingers and neck, and large tongue. Mentally, children with Down syndrome will fall behind other children of the same age, and may also suffer from ASD and ADHD. Furthermore, they are at greater risk of suffering physical disabilities, including hearing difficulties, a squint, congenital heart defects and hypothyroidism.