yes they are brother and sister
No, as far as we know Longtail did not have a mate, and Mousefur never had kits.
no yes he ambushed him mousefur and thornpaw and killed runningwind.
really his family is unknown his father is unknown but his mother is one-eye (white-eye) and his sister is mousefur Edit: Runningwind's only sibling is Mousefur. His mother is White-eye (One-eye) and his father is Sparrowpelt (Halftail), neither of which parented another litter.
Runningwind is a ThunderClan Warrior when Firestar was first introduced into the clan. He became friends with Firestar and Graystripe. He was killed by Tigerstar and a group of rouges. He lived from the end of Bluestar's prophecy to series 1 book 4 rising storm. His death was found out when Mousefur came back to camp all bloody and led the ThunderClan deputy, Fireheart to the spot where Runningwind's body lay. That led to Firestar chasing Whitecloud into the Thuderpath where he got hit by the car and then the fight between The patrol and the rouges soon to be joined by a RiverClan patrol led by Graystripe. Sorry if this is a lot of info! Just luv warriors!
Bluestar, Redtail, Spottedleaf, Lionheart, tigerclaw, Whitestorm, Darkstripe, Longtail, Runningwind, willowpelt, Mousefur, Dustpaw, Grawpaw, Ravenpaw, Sandpaw, Firepaw, Frostfur, Brindleface, Goldenflower, Speckletail, Halftail, Smallear, Patchpelt, One-eye, and Dappletail
unknown yellow or amber
No, Mousefur never had any kits in the Warriors series. She was unable to have kits due to infertility.
No, he doesn't.
Runningwind was killed by a pack of dogs during a battle in the book series Warriors by Erin Hunter.
Thornclaw and Spiderleg.
Mousefur is a character in the Warriors book series by Erin Hunter. She is a loyal and wise warrior of ThunderClan who is known for her practicality and straightforward nature. She plays a significant role in the series, offering guidance and support to her clanmates.
Thornclaw. Then Spiderleg.