B.M.
My middle daughter was very clingy. Broke my mother's heart, that her granddaughter didn't want anything to do with her. Didn't want the pediatrician to look at her. Didn't want anybody. It didn't last. I can't remember when, but she is 5 now and just fine.
As for walking, they walk when they are ready. I have one that took her first steps at 8 1/2 months and another that waited until he was almost 14 months to walk.