lol yes i have seen this first hand.. just watch her for the symptoms of chameleons disease.... 
1. grown up enters room.. has civilized conversation 
2. child makes eye contact with adult 

3. child climbs onto adult 
4. adult becomes like child.. eg. playing in the toy room with all the noisy toys
and misbehaving with the little ones.. blending in like the chameleon so you are unsure which is the kid (hehehhee)

Felicity has all the classic symptoms of being a "carrier" of this terrible disease.. it is suggested that you keep her far far away from any children 