Answer here with the account of a sibling (give the link). This way we mods won't ban for a duplicate account when we see the IP. Here are the rules with sibling accounts:
You cannot vote up the other sibling. This can easily end up going into the realm of spam up-voting. You might feel more obligated to vote up your brother or sister. So just don't do it.
Don't answer your sibling's question. YOU CAN JUST TALK TO EACH OTHER IF ONE OF YOU KNOWS THE ANSWER! Using the Pokebase is not needed if one of you knows the answer and will only be considered point grubbing.
This only applies if your sibling uses the same router as you. Also, if you are related and live in different households 1 and 2 still apply.
Users who have previously had problems with duplicate accounts cannot have sibling accounts.
By you following these rules we mods can be sure that you aren't using a duplicate account to get yourself more points. So break any of these rules and you might find yourself liable to a ban.
Please also make a post here if you know of any users who connect to the same public or school network as you do. If we know that a network is used by more than one person and that a problematic user connects to it, we will not block the network and only block the individual user. Normally, we would block both the user and the network, but if we know that this would have adverse effects on other users, we will arrange a workaround.