If the password is the password to Windows, and if it is the administrator password, the only way to get past it within Windows is to reinstall the operating system. There are programs that can sometimes help to get past a password by booting in place of Windows, but each version of Windows has become more secure, and so these programs may only provide a partial solution, with some or a great deal of information still lost. Windows can be further secured optionally in ways that make all these programs useless, but it's unlikely that she has done that.
If the password is to the BIOS, there's no way to get past it without resetting or erasing the BIOS password. Some computers provide a way to do this, by removing a battery or moving a jumper, others do not. Those that do not require that the BIOS be physically replaced, e.g., with a soldering iron, and that is a significant undertaking.
It's important not to forget passwords. Systems are inaccessible without them, by design, and every generation of computers makes it harder to gain access without a password. In many scenarios, access is already impossible.