My 2 1/2 month old has a single beat ankle clonus. It stops when his foot is held. He is ahead on milestones and has good head control. Is this normal?

Clonus. This can be normal, but the clonus test is done as only part of a full neurologic exam in a child. Your childs doctor will be the one to evaluate and complete the exam. Ask questions as well at that time.
Yes. Ankle clonus is normal in infants with their immature nervous system and may be seen up to about 1 year of age.