EastEnders spoilers follow for Monday’s episode (July 8), which is available to watch now on BBC iPlayer but doesn’t air on BBC Two until tonight.

EastEnders’ Stevie Mitchell has revealed a shocking family secret in the show’s latest episode.

Last month, Billy was blindsided when Stevie’s secret son Teddy – and his sons Harry and Barney – arrived in Walford, but he eventually welcomed his brother to the family.

In today’s episode, Billy was preparing to say goodbye to Honey, who was going to look after her aunt, when Mo reminded him that it was Stevie’s birthday today.

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As Stevie seemingly bought a birthday card for himself, Billy set about organising family drinks in the pub, with Will determined to make a big effort for his grandad.

When Billy said that he wanted to light a candle for his mum, he explained to Will that his mum and dad have the same birthday and that he didn’t know where she was now.

Teddy gave his dad a card in the café and urged Stevie to stop lying to Billy about how long he and his mum were together – a conversation that Phil overheard.

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Billy decided on a theme for the party, and recalled a childhood memory where their parents took them to Southend Pier on their birthday and bought them rock and candyfloss.

Will’s preparations failed as he couldn’t buy cake and balloons, but Teddy saved the day when he returned to the pub with sticks of rock and candyfloss.

Meanwhile, Phil got Ritchie to find out what Stevie is hiding, before Billy called round to convince him to come to the party.

Stevie was delighted by the surprise party, and Billy was pleased when Phil later arrived, having heard back from Ritchie.

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Billy made an emotional speech in tribute to both his mum and dad and after he raised a toast and hugged his dad, Phil told Stevie what he knew and threatened to tell Billy.

Back at the house with Phil and Teddy, Stevie gave Billy the card that he wrote to his mum Val, and Billy assumed he knew where she was.

Stevie then revealed that his mum died back when Billy was nine and said that her death was his fault.

But how did Stevie cause Val’s death?