On the pig's back phrase informal
Having become popular, made a lot of money, had fortunes, or had a comfortable life.
After appearing in that popular and successful film, Mary must be on the pig's back.
Those, who've been on pig's back since they were born, will never understand the hard life that I'd gone through to be rich as I am today.
Nothing but fortunate chance
If a person has the devil's own luck, he or she has extremely good luck.
Be fortunate that
This phrase is a literal translation of the Irish 'ar mhuin na muice', which dates back to the 17th century.