Adorably, Harry gave the toddler a mock warning.
The newlywed couple have openly admitted their desire to start a family.
'Of course,' Harry told the BBC following his engagement announcement to Meghan. 'You know, one step at a time. Hopefully we'll start a family in the near future.'
During a visit to Northern Ireland in March, the former Suits star admitted their baby plans when speaking to the couple who own Shnuggle, an innovative baby product company.
'I am sure at one point we will need the whole thing,' Meghan told the couple. 'It’s very sweet.'
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This week's New Idea Royals podcast delves into what REALLY happened at Prince Louis' royal christening.