HH Pinkie was one of our older seedlings and we were about three years into growing seedlings. It's parent was a "flash in the pan" variety that was around for only a year or two and is no longer seen. It's name was garbled in our records. We never used Pinkie for breeding after the only batch of seedlings were not very good. We stopped growing it about 20 years ago. It is a strong grower and has pretty flowers but the centers do not last very long.
HH Serenity on the other hand was a breeding success done from Margaret's hand crossing for several generations and it has about 80% of the genes of the all time winner Pam Howden. It is one of the only flowers that is line bred on Pam Howden and that is because Pam Howden makes so few seeds for most people. We never , ever, got a seed from Pam Howden despite getting a different version of the stock(an open center sport was tried) . I was the designated pollen collector and was tasked with finding ripe flowers to provide pollen for her hand crosses. The best seedlings were crossed back with each other and selected until Serenity was the result. It has won best waterlily in show. HH Letitia is a seedling of Serenity and it won a medal here and in the UK.