Like about being in a big family:
Your elder siblings will look after you if anything happens. There will always be fun in the house, and laughter. You can ask for help because there are so many siblings that have different passions.
Don't like about having a big family:
It's always going to be cramped in the car or in the house. You have to wait a long time for a turn in the shower or toilet. Someone will intrude into your personal space of the room maybe.