If there's one nature documentary style show that's wormed its way into our heads and hearts its Animal Odd Couples. Last week we met Baloo and Shere Khan there, fell in love with Della and her ducklings all over again, and discovered that dogs and deer can have an utterly wonderful relationship in the right circumstances. Tonight we're catching up with Liz Bonin and co for the last installment to find out how a hippo can become part of the family, and witness some more wonderfully unlikely animal friendships blossoming.