We have all faced our parent telling us to play with our little sibling or spend more time with the family instead of the team. This is often hard to hear, because you don't want to abandon the team or miss out on any of the fun they are having. With this being said it is also important to spend time with your families, but I do have to say it is not always at the right time. At tournaments your parents might always tell you to do be doing things to prepare for your games, but then tell you to spend time with them. Being with your teammates and having some quality bonding time is preparing for the games as well and will build team chemistry. This will help your performance as a whole.
Sometimes it is hard to choose between family and sports, but you must make the decision. Sometimes it is easier than others depending on the situation or how serious it is, but athletes should always put their family first in times of need, family stays with you forever and should be taken care of. With this being said, if the family dilemma is an extremely small one, like your sister wanting to play a game, you can sometimes get away with choosing to hangout with your teammates instead. This all depends on the situation and your decision making. It's not always going to be easy. Sometimes you are going to have to ditch your team when you really do not want to, but trust me they will understand and they will have to make that decision themselves too. Everyone must choose the days they dedicate to family and other things.