No, Hollyleaf did.
No because the kits are Crowfeather's and Leafpool's and Ashfur never fell for Leafpool
Brindleface. Brindleface was murdered by Tigerstar, when Ashfur and Ferncloud were apprentices. Their father was Whitestorm
He isn't a warrior but Jayfeather is pretty miserable. Or Crowfeather, Ashfur...
No, Hollyleaf does. It may seem like Squirrelflight did but she didn't 'cause Hollyleaf admits that she did kill Ashfur in Sunrise.
Ashfur tries to murder Squirrleflight, Hollyleaf, Lionblaze, and Jayfeather because when Brambleclaw and Squirrleflight got in a fight Squirrleflight grew close to Ashfur. So when Squirrleflight and Brambleclaw make up and become mates Ashfur get furious. So when the clan believes Squirrleflight had Brambleclaw's kits. Ashfur blocks the only way out of camp when Squirrleflight and her kits are still in camp when there is a fire. Squirrleflight tells Ashfur that they aren't her kits but she doesn't tell whoes kits they are. In the book Sunrise Hollyleaf murders Ashfur before a gathering because he was going to announce that Hollyleaf and her littermates weren't Squirrleflight's kits. So when Leafpool tells Hollyleaf she knows that she killed Ashfur Hollyleaf runs away to the underground tunnels. they collapse on her and she died. Some people believe she is still alive. (Hollyleaf, Lionblaze, and Jayfeather work out that Leafpool is their mother. While Jayfeather was dreaming StarClan came to him and gave him a crow feather. Jayfeather tells his littermates that Crowfeather from WindClan is their father. Hollyleaf announces at a gathering that Leafpool and Crowfeather are her real parents. Crowfeather gets furious with Leafpool and Leafpool backs down from her position as a medicine cat.)
Ashfur did not kill Squirrelflight in any book. He did attempt to harm her in "Sunset" (Warriors: The New Prophecy series) by attempting to push her off a cliff, but Squirrelflight survived. Ashfur's actions were driven by his jealousy and betrayal, but they did not lead to Squirrelflight's death.
i don't think she should go into the dark forest. she didn't kill ashfur for joy, she killed ashfur shortly after a confrontation with their mother, squirrelflight, who turns out to be not their mother but their aunt, as it was leafpool and crowfeather who are the actual parents of hollyleaf, lionblaze, and jayfeather. Hollyleaf already knew about the true story about who their parents are, but during the confrontattion with ashfur squirrelflight revealed the secret to ashfur and so hollyleaf killed him so that the secret would not get out, but eventually she becomes so torn apart by guilt that at the next gathering she explains the whole thing. she didn't kill ashfur to save firestar, anyway and she doesn't belong in the dark forest because in the last book of the power of three she dies because of a cavein.
Ashfur
No, it was Ashfur.
*Spoiler Alert* No Hollyleaf does.
No, Ashfur would never try to kill Squirrelfight. He loved her but tried to kill Hollyleaf, jayfeather, and Lionblaze to get revenge on her. Then she revealed they were not her children and he didn't kill them.
Hollyleaf convinced Ashfur to kill Squirrelflight's kits by revealing the secret of their true parentage. This revelation led Ashfur to seek revenge against Squirrelflight for lying about who their father really was.