Hello , my son turned 10m a few days ago and he has not hit several milestones. His pediatrician did not ask us to come in for a formal 9m checkup. He cannot crawl, cannot pull to stand. He is just starting now to get into a sitting position by himself from lying on back. He does not really respond to his name, doesn’t point, doesn’t imitate, doesn’t wave. He smiles from time-to-time but it takes a lot to get him to smile. He babbles but it seems more to himself than communicative. He’s also recently started clapping but it seems more to himself than imitative. I’m concerned- I’m a ftm. Is this something anyone else has experienced? Please give advice and share insight- thanks so much.