Weight loss in cat after death of sibling

Question
Dear Erin,
I adopted two litter mates (sisters) 5 years ago.  One had to be euthanized on June 23rd because of (drs are not sure but suspect maybe cancer or severe IBD).  She had a feeding tube and I didn't want her to suffer anymore so had to let her go. Well, that was after moving 15 hours from MA to NC on June 20th.  My animals have been through a lot.  I adopted them from someone that was going to drop them off at a shelter.  Just when they were becoming settled and happy, I introduced a big male cat into my home and it was a disaster but I would not bring him back to the shelter because he is old and no one wanted to adopt him.  Then I sold my condo. and moved to an apt. for a year and then this past June 20th, I moved them to NC.  Well, the surviving sibling "Riley" is losing weight now.  She misses her sister terribly and it is breaking my heart.  I know this because I opened up a closet door a week ago to get something and the surviving litter mate ran in.  She smelled her sister's bed and cat carrier and was desperately searching for her sister.  It broke my heart!  I couldn't believe how desperate she was acting.  What in the world can I do to help her?  I can't stand to lose her too.

Answer
Its obvious your cat is suffering from depression, losing a cat is very heartbreaking, and probably more so with the cats common companion.  Do you have other cats or is she the only one?  If so you can try introducing a kitten of the opposite gender, a very young kitten no more then 6 to 8 weeks old.  If you do have a cat hold out on the adoption.  If you dont want to adopt another kitten the only other option is to make sure she eats at least twice a day and have her checked by a vet to rule out any parasites or other disease.  In the mean time try feeding her soft food, she might like some of that!