They had five children and all went well until Henry died. Instead of choosing Otto her eldest son to succeed to the throne, she chose her favorite Henry Jnr.
This upset both sons who turned on her rather than each other. Especially when they found she had been emptying the royal coffers in aid of charity.
When Otto eventually came to power she was forgiven, but he probably breathed a sigh of relief when she retired to one of the convents she had founded.