By Jeremy Ross

(CBS) – The family of missing University of Illinois scholar Yingying Zhang is making an emotional plea to the highest office in the land.

CBS 2’s Jeremy Ross reports on what they asked for and their message to the media.

During a news conference Tuesday, Zhang’s mother searched for comfort as the scholar’s boyfriend vowed not to return home without her or her body for burial.

Zhang disappeared June 9 on the U of I campus. Investigators believe she is dead, killed by former graduate student Brendt Christensen, 28.

“I had promised, I will protect her,” said boyfriend Xiaolin Hou.

He denies the allegations, and the location of the victim’s body remains a mystery.

Now, the family is asking the White House to help them by offering more federal resources to help solve the case.

A Go Fund Me page has helped the family stay to look, fund their own investigation and keep the 26-year-old’s name in the public. They hope to raise $500,000.

“We cannot repay your kindness,” said Hou. “It is a shame that the only thing we can do, is say thank you, with all my heart.”