The Drinking birds of the Alien series.

So fun fact Ripley isnt the only star to come back time and time again in the Alien movies and before anyone says anything.its not Bishop.

Its the drinky birds. In Alien their on the main mess hall table. In Aliens their Sulaco's mess hall and in Alien 3 their on Andrews desk. Maybe its some kinda of Wayland-Yutani tracking device or maybe its just some thing they stocked at their gift shops....no matter it turns up in Alien Isolation too.

Those creepy fucking birds