Fixing Grub on a multi OS boot

[stan]

I just installed 5.10 on a laptop that had Debian and FreeBSD on it.
I was careful with the partion editor, to replace only teh Debian partion,
now grub only offers me ubuntu as a choice. Grub replaced the existing
bootlader BYW :-(

How can I fix this?

-- 
U.S. Encouraged by Vietnam Vote - Officials Cite 83% Turnout Despite Vietcong Terror 
- New York Times 9/3/1967