 Their first daughter was born in the following year (1070).On 12 February 1074 their son Conrad was born at Hersfeld Abbey, where Bertha stayed while Henry was fighting against the Saxon Rebellion, and was baptised in the abbey three days later.After Henry's victory against the Saxons, he arranged for an Imperial Diet at Goslar on Christmas Day 1075 to swear an oath recognising Conrad as his successor.