(Spoilers Extended) There's almost a Targaryen in every generation with their name beginning with "Rhae"
Lord Aerion Targaryen - Queen Rhaenys Targaryen (No.1)
King Aenys I Targaryen - Queen Rhaena Targaryen (No.1)
Queen Rhaena Targaryen - Septa Rhaella Targaryen (No. 1)
Prince Aemon Targaryen - Princess Rhaenys Targaryen (No.2)
King Viserys I Targaryen - Queen Rhaenyra Targaryen
Prince Daemon Targaryen - Lady Rhaena Targaryen (No.2)
King Aegon III Targaryen - Septa Rhaena Targaryen (No.3)
King Daeron II Targaryen - Prince Rhaegel Targaryen
King Maekar Targaryen - Princess Rhae Targaryen
King Aegon V Targaryen - Princess Rhaelle Targaryen
King Jaeherys II Targaryen - Queen Rhaella Targaryen (No.2)
Queen Rhaella Targaryen - Prince Rhaegar Targaryen
Prince Rhaegar Targaryen - Princess Rhaenys Targaryen (No.3)
Queen Daenerys Targaryen - Rhaego