As Glen Campbell continues to fight against the effects of Alzheimer's disease, his daughter, Ashley, continues to fight for funding for research on the devastating illness. The 26-year-old traveled to Washington, D.C. on Wednesday (April 24), along with her ailing father, to appeal to U.S. Senators to continue pursuing a cure for Alzheimer's.

"A person's life is comprised of memories, and that's exactly what this disease takes away from you -- like a memory of my dad taking me fishing in Flagstaff when I was a little girl or playing banjo with my dad while he plays guitar," Campbell's tearful daughter, who plays in his band, testified. "Now when I play banjo with my dad, it's getting harder for him to follow along -- and it's getting harder for him to recall my name. It's hard to come to the realization that some day my dad might look at me and I will be absolutely nothing to him."

The 77-year-old music legend, who was diagnosed with Alzheimer's in 2011, was forced to retire from touring because of the effects of the disease. But his wife, Kim, says he isn't giving up his entire music career just yet.

"Glen still wants to record, but it's just a matter of if he's able to," she explains. "It just gets more and more difficult for him all the time." She adds that he still enjoys getting out as much as possible.

"The other night we went to see Merle Haggard and hung out with Toby Keith on his bus," she continues. "Everybody played different songs and had a great time."

Glen will release a new album, See You There, on August 6. The CD features several of his biggest hits, including "Wichita Lineman," "Galveston" and "Rhinestone Cowboy."

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