I’m sorry to read this and can see you’ve had a lot of good advice that I shan’t repeat.
What I will say is that SS as harsh as they can be, are usually focused on keeping families together unless very strong evidence is provided that the child is in danger. In this circumstance you’re being treated as guilty until proven innocent and that’s so awful to go through, I hope it gets resolved quickly and baby is back home soon.
When SS were involved with my family after DS had come home from NICU and DD was still in, they were trying to prevent my DD coming home because they thought I was st risk of PND and were questioning how I was coping with one Baby let alone two... I was livid but I made sure to do the following:
Timeline of daily activities with DS, including keeping with schedule of meds and feeding (in your case I’d write a timeline of the day in question with the pertinent points you’ve raised such as the telephone call request for Calpol, get a printed call history to include as evidence of their call to you.)
Always keep calm when under fire, it’s hard when the route of questioning takes a judgmental route, but keep calm, don’t feel the need to rush your answers, be passionate but try not to go in the defensive outwardly.
Have a third party witness to any and all meetings with the SS. My FIL would come suited and booted, was polite and rarely spoke during the meetings, but his presence was useful.
Take notes, have the SS sign off on any and all actions they have advised you take (if applicable).
Get any third party evidence you can, CCTV at the nursery if there is any, staffing levels on the day of the accident/event.
If you feel it will help, take it above your assigned Caseworker and contact either the manager of your Local Authority’s SS Department or your local MP.
Contact www.familylives.org.uk/advice/your-family/social-services-and-your-family/social-services-and-your-family/
Sorry if it’s not clicky, good luck @napol I’m so sorry you’re going through this 