The 'Mary Poppins Return's actor was in awe of the high energy of his elderly co-star - who appeared in the original 1964 Disney classic - and enjoyed gossiping with him on the set of the highly anticipated sequel.
The 38-year-old performer told Collider that he loved shooting scenes with the legendary 'Chitty Chitty Bang Bang' actor and said: ''It was like the best two days ever. I aspire to having that much energy in my life, someday, much less at 91.
''We were in the scene together, and we were just huddled off in the corner, and I was asking questions about 'Bye Bye Birdie'.
''You want to talk about a run -- that guy went from debuting on Broadway in 'Bye Bye Birdie' to getting 'The Dick Van Dyke Show' to filming 'Mary Poppins' like, on his hiatus. If anyone has a right to be retired and chilling, it's Dick Van Dyke!
''And yet he's with us singing and dancing, and it was really thrilling, you know, just to swap Broadway stories about him...''
'Mary Poppins Returns' stars Emily Blunt as the magical nanny who returns to help the Banks siblings and Michael's children decades after her original visit because they are going through a difficult time in their lives.
Dick is appearing in the sequel as Mr. Dawes Jr, the chairman of Fidelity Fiduciary Bank.
Lin-Manuel gushed that starring in the sequel - which is helmed by 'Chicago' director Rob Marshall - was a dream come true.
He added: ''I mean, it's amazing. Because, you know, there are dreams come true moments; getting your show on Broadway, getting to be in a movie.
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