My 9 month old daughter is perfectly fine with adults (unless its either of her grandpas or a particular uncle). She will happily crawl over to other parents, smile, wave and offer things and generally engage. The problem occurs when their children come over. If they crawl toward her to try and engage she immediately turns and crawls away as fast as she can and just clings on to me as if theyre the most terrifying thing she has ever seen. If she could run she would. Is this normal?