Knut's "dad" passes away suddenly.

Jesus, it's one heart-wrenching polar bear story after another. From Yahoo! News:

Hundreds of Germans flocked to the Berlin zoo on Tuesday to mourn the sudden death of the popular zookeeper who raised celebrity polar bear Knut.

[...] Doerflein, who shot to fame as Knut's surrogate father after the tiny cub's mother Tosca rejected him at birth, was found dead in his Berlin apartment near the zoo on Monday.

The 44-year old zookeeper with a thick black beard won the admiration of many in Germany and abroad when he stayed with the polar bear around the clock for 150 straight days, handfeeding the cub milk and porridge through the nights.

A modest man who had worked in the Berlin Zoo for about 28 years, Doerflein said he had received love letters and propositions from female fans after he became Knut's "dad."

"I wrote a letter to express my grief," said crying teenager Jennifer Hennig, standing by a collection of cards and flowers near the enclosure where Knut, now a burly grown bear, paced around.

"I didn't know Thomas personally, but he became somewhat of a friend to me. It hurts when you lose a friend," Hennig said.