Honestly, it took our ate like 2-3 months bago siya fully okay na with her kuya, pero the jealousy and acting out came in waves pa rin for a bit after that, laging nagbabago ang dynamics haha. What helped us most was making her feel she still has special time with us (nag-assign kami ng "ate duties" na parang she's the big girl in charge, plus one-on-one time kahit 15 mins lang), letting her help with baby care if she wants, and being honest na it's okay na siya mag-feel ng weird kasi ito talaga ang biggest change niya, ang pag-normalize lang ng feelings na yan, hindi pag-ignore, made a real difference sa aming case. Give her patience and reassurance, pero don't stress yourself trying to make it perfect right away; ang adjustment na yan ay magiging normal lang eventually.