I found twins in my nursery this morning. They're mixed so they're priced at just 5K each. I've put them up for bid to make sure that they go together, so just bid 5K on each.
http://www.ponyisland.net/index.php?src=pets&sub=profile&pet=13744128&usr=386264
http://www.ponyisland.net/index.php?src=pets&sub=profile&pet=13744129&usr=386264
