Uhhhhhhh ... that's not a cat toy!!
Serena Williams' adorable 5-year-old daughter occupied herself by playing with a cat toy -- also referred to as a tampon -- in a TikTok video posted by the newly retired tennis legend.
The clip shows Olympia unwrapping a tampon and pushing it out of the applicator in the bathroom.
Williams asked Olympia what she was playing with ... and she responded, "It's a cat toy for Karma."
Serena was clearly amused, at first -- holding back laughter and making faces at the camera -- that is until Olympia continued to unwrap more "toys.