Wesley Williams behaved as if nothing had happened after murdering his ex-partner and her son, a court has heard.
Yvonne Walsh, 25, and her seven-month-old son Harrison were found dead in separate rooms with the curtains drawn at their home in Birmingham in May this year.
Mr Justice MacDuff said Williams' subsequent behaviour, which included posting messages on Ms Walsh's Facebook page and visiting friends, demonstrated how unconcerned he was at what he had done.
The judge told a completely impassive Williams:
You are the only person who knows precisely why you acted as you did, but it is clear that you could not accept being rejected by Yvonne Walsh when you were proposing or intending to propose marriage, and she wanted no further part in a relationship with you.
And you decided to kill her - in fact to execute her.
It was your decision, casually taken, that she had to die.
And then you killed Harrison as well, probably as he lay sleeping in his cot.
More top news
For the first time in its 34-year history, the editorial board of USA Today have taken a side in a presidential election race.
Thousands of vehicles have been confiscated by police forces because their drivers were either not insured or did not have a valid license.
Across all of the Help to Buy schemes, 185,000 homes were brought, including 150,000 properties to first time buyers.