Daily Mail has a story on it.
'Justin Welby IS my son': How Winston Churchill's aide confessed that Archbishop of Canterbury was his secret lovechild two weeks before he died... and never got his last wish to see his boy again
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Macklin, 56, is the son of Lady Shelagh Montague Browne from a previous marriage and is a renowned round-the-world yachtsman.
He had growing suspicious that Sir Anthony was Welby's father and the family used to joke about the striking resemblance between the two.
In early 2013, in a nursing home, Sir Anthony said he would like to meet Welby, who was Bishop at the time.
Macklin phoned the Bishop's office and made the request to Welby and also told him that he thought Sir Anthony, who was a friend and former colleague of his mother Jane Welby, was his father.
The surprised priest reportedly listened carefully but said he will discuss it further once the process of him becoming Archbishop of Canterbury was all over.
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According to the newspaper, the family had long discussed the striking resemblance between the Archbishop of Canterbury and Montague Brown - and Welby himself was aware of the rumours.
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'To find that one's father is other than imagined is not unusual. To be the child of families with great difficulties in relationships, with substance abuse or other matters, is far too normal,' he [Archbishop Welby] said in his statement.
www.dailymail.co.uk/news/article-3530902/This-comes-complete-surprise-Archbishop-Canterbury-s-shock-discovering-illegitimate-son-Churchill-s-private-secretary.html