When MSLS were about 1 year old, ES was almost 4 years old. At that time while the twins thought they were playing with che che, ES would complain that they were disturbing.
MSLS are now almost 22 months old, and ES is four and a half. As the twins grow, they begin to learn how to play certain games. And therefore, sometimes the three sisters would play together and you will hear laughter here and there.