@kiltguy2112, thanks for the help.
@Andy19, that certainly hasn't been easy for you or your daughter ― let's check it out. Is your daughter trying to play music on her Google Pixel 4A, in which the music becomes garbled or is she giving command to the Google Assistant on her Pixel phone to play music on your speaker? Also, could you tell us what kind of speaker you have? Are your devices linked to the same account and under the same Wi-Fi network?
It would help a lot if you could do a sequential reboot to refresh all connections. Unplug the power cord of your router followed by your Nest speakers. Plug them back in after 3 minutes starting with your router. Restarting the phone might also help.
Keep us posted.
We haven’t heard back from you, so I'll be locking this thread in 24 hours. Feel free to create a new one if you have more questions or have other concerns in the future.