Developmental milestones will vary greatly by individual for several reasons. First of all, children naturally develop at different rates, and each individual's genetics will play a role in how they develop. Additionally, Coffin-Lowry syndrome expresses much more mildly in females; developmental milestones in females can cover the range from severely intellectually disabled to near normal. Therefore, the information below is primarily aimed at males. Even among males, there is variability in how the syndrome is expressed. Development can also be affected by the presence or lack of hypotonia, hearing loss, and other secondary characteristics and symptoms of CLS. Prior to birth, growth is usually normal with normal birthweight. Males usually fall below the 3rd percentile in height.
Note: The following information is anecdotal, based on data gathered from letters written by family members of individuals affected by Coffin-Lowry syndrome.
Walking: Usually somewhere around 2-3 years. They may skip crawling or have some other means of getting around prior to walking, like scooting on their bottoms. Many children have a more or less normal gait with mild coordination and balance issues. In some cases, walking may appear normal if unsteady for the first few years, and then somewhere between ages 4-7, the child's gait may slowly change to a more wide-stanced gait, knees somewhat bent. Sometimes the left leg will drag behind the right. Often this so-called "ataxic" gait is associated with drop episodes, and the two characteristics will emerge about the same time. Both are most likely neurological in origin.Speech: Speech is always impaired in CLS patients. However, there is some variability. Some patients acquire substantial oral communication, whereas other patients, especially in combination with hearing impairment, never speak. A few basic sounds emerge between birth and 4 years, then between 4-6 years, 2-3 word short sentences usually emerge. Speech will continue to evolve and grow slowly over many years. Most have articulation problems due to hypotonia, but can generally be understood even by strangers. Most have problems with the more developmentally sophisticated sounds made at the back of the tongue, such as the hard "G", "L", and "R", and will substitute sounds they can make in their place, so that "good" becomes "dood", and "love" becomes "wuv". Despite the limited verbal abilities, the communications skills are good. They usually understand (receptive language) much better than they can speak (expressive language) so their understanding is often underestimated.
Toilet Training: Most children with intellectual disabilities can be toilet trained by age 7, including Coffin-Lowry children. Watch for the normal signs of readiness, i.e., awareness that they have soiled, and a desire to be changed. As with all other things, toilet training will take longer with CLS children. Children need to be able to follow at least 5 actions in sequence to be toilet trained, so they may need assistance for some years. Some are never toilet trained. Watch for constipation, which is very common due to low muscle tone and inactivity and can lead to painful and dangerous bowel blockages.
Self-Care: This will depend on the degree of delay in gross and fine motor capabilities. Many will eventually learn to handle their own personal hygiene and dress themselves, but some may always have trouble with fasteners such as buttons or tying the laces of their shoes. Pull-on pants, pull-over tops, and shoes with Velcro closures are wonderful for this and help give them a sense of independence and accomplishment.
Reading/Writing/Math: This varies a great deal by individual; writing is dependant on their fine motor control. Many will learn a few simple words - their name, the names of their family members, etc. A few do much better. Some do not learn to read or write at all. They have good memories and will memorize facts but are not necessarily able to apply the concepts. For example, they may rote count to 20, but can't tell you how many fingers you are holding up.
Social/Emotional: Developmentally, this is the area least affected. Most Coffin-Lowry individuals are quite intact emotionally. They are capable of love, anger, jealousy, depression, joy, just like everyone else. They tend to be polite, affectionate, and very outgoing. A minority exhibit behavior issues.