my lo does something similar to others - the commando crawl lol bless! - do not compare your child to other peoples because 1. more than often there is an exageration especially if its from a person who know a person who has a child who blah blah blah lol
my boy he rolled early-ish just shy of 4 months, could hold his head up by himself within a couple of days so we thought wow he is going to be an early walker etc etc, nope, he didnt walk until he was 20months old, he could do it just didnt want to, he said his first word at 9 months so again we thought he would be a really good talker nope he literally learnt mumma, dadda, no, hair and nanna and that was it until he turned two when he picked up maybe 20 more words between 2 - 2 1/2 we were thinking of going to go to a speech therapist but all of a sudden a couple of moths back he started talking really really well he is now ahead on all aspects of language, amount of words, pronounciation and amount of words in a sentance, now he looks like he is mega ahead
all kids hit milestones at different times and although i know just how hard it is when you can see people's babies and children streaming ahead of yours do not compare because your lo might all of a sudden zoom past them!
my mantra was i am not worried, i know he can talk/walk he is just lazy and what 30 able year old has their mum come to work to translate their babble and their dad carrying them around the office? none!