No. When Marie Antoinette was executed in October 1793 two of her children were still alive (her first son died in 1789 of tuberculosis and her second daughter died at 1 year old in 1787). Her last two children stayed in the prison of the Temple, where the Dauphin (also known as Louis XVII) died in 1795 of scrofula, her last child Marie Therese was allowed to leave for Vienna in late 1795 and actually lived on and died in 1851.

To broaden the question, were the children of aristocrats guillotined like their parents?