The room was much quieter now that the playgroup kids had been taken away by grandparents and friends. The mothers remained. When Suze had rung in to request background checks on all the playgroup mums, she’d said the station was almost silent. Normally a buzz hummed through Woden police station, the sound of colleagues on the phone, in interviews, briefing the team, discussing surveillance. But between the officers out at Parliament House and a missing child, it was like a morgue. On top of that, everyone went quiet when a child was involved in a case; the usual black humour was suppressed, and the competitive piss-taking too.

Suze asked if any of the mothers had taken photos of the children on their phones this morning; they might have captured someone or something in the background, outside the fence. But none of them had.

Shifting uncomfortably in the hard-backed chair near the kitchenette, Caruso checked his notes. Imogen Lawrence. Mother of twin boys. Brown bobbed hair, average size. Jeans and a spotty jumper. Wouldn’t stand out in a crowd. Friendly. Wanted to help.

‘Where exactly did you see Bella last?’

‘I couldn’t really say. Bella was in here near the dressing-up box.’ Imogen pointed to the far corner. ‘But then she was also outside in the cubbyhouse with my boys. They were going in and out.’

‘Did any adult go outside with the kids?’

‘Yes, I think Julia was outside. Or was it Mel? Oh, I can’t remember.’

The woman put her hands to her face and the tears flowed. Her hair was damp against the sides of her cheeks. Tears mixed with sweat from racing around the streets earlier.

Passing her a box of tissues from the shelf next to him, Caruso smiled encouragingly.

‘Was anything happening in the room?’ he pressed. ‘Any kind of distraction inside?’

‘I don’t know.’ Imogen blew her nose loudly and wiped her cheeks. ‘There are always distractions. Children crying, toddlers arguing, stuff being dropped on the floor. My twins are always distracting someone.’

‘What do you mean by that?’

‘Oh.’ Imogen hesitated. ‘They’re not very good at interacting with other children.’

Caruso waited to see if she would say more.

‘I … we … it’s just that … they get … um … easily frustrated.’

Did the twins have behavioural issues? ADHD? Had they hit Bella? Was that why she’d disappeared? Was she scared and hiding from the boys? Imogen was the one who had called triple zero, he wouldn’t forget that. But none of these mothers seemed to have any concrete information; no-one remembered Bella’s movements. Through the window, he noticed a new mum with a toddler in hand.

‘Who’s that coming in the door now?’

‘Oh no.’ Imogen’s hand flew to her mouth. ‘It’s the Thursday afternoon group. I’ll have to go and tell them.’