Negative Energy Affinity Mount / Animal Companion?

[SoonerTed]

I'm playing in a party with all negative-energy affinity characters. As such, the healers all heal with negative energy.

Are there animal companions (druid/ranger/hunter) that have negative energy affinity?

Are there any mounts (for cavaliers) with negative energy affinity?

[Chess Pwn]

If you're a dhampir I think there's a feat that lets your animal companion count as undead, vampiric companion http://www.d20pfsrd.com/feats/general-feats/vampiric-companion it will take a while though.

[Tirq]

Summoners can ride their Eidolon, and make them count as Undead for that purpose. There's also this wonderful feat that does it as well, but I don't quite remember the name. I'll have to look it up later.

[Treefolk]

Discuss with the GM but probably the simplest solution is to create a feat that applies either the zombie or the skeletal (Ii'd lean towards skeletal) template to your AC. There's precedence from Skeletal Summons and Celestial Companion, shouldn't break the game power-wise and sounds like it would be a flavorful feat for your current group.