So what? Who really cares? Why is it so important? Perhaps Amaral was referring to sedative as defined by the dictionary. For God's sake, it is hardly libellous.
Parents give their children Calpol all the time. It's an over-the-counter medicine. Practically everyone I knew with babies and young children used to stuff them with Calpol at night if they had a cold/were fussy. Why would it be libellous to suggest that the McCanns used Calpol to calm their children?
What is more likely is that the McCanns DID use a sedative - not Calpol but something else, something much more powerful. Amaral was on the right scent but not quite right in the details. And if the McCanns did use a much stronger sedative, then that would account for how the twins slept through the night when Madeleine allegedly disappeared.
That is probably why the whole Calpol debate is such a hot potato - an attempt to throw everyone off the scent just when they were getting close. So predictable, it's actually quite funny.
That is what happens in medical negligence cases. There will be endless nitpicking, derailing, obfuscation, failure to look at the whole picture, apportioning blame on others rather than taking responsibility. As soon as someone starts to get near the truth, there will be a dissection of the minutiae and an attempt to discredit the whistle-blower. In fact, a full-blown assault on the whistle-blower or the person trying to find the truth.
The Calpol red herring is a good case in point. Amaral was on the right track - some of the finer details are probably not there but sniffing in the right direction. So there will be a full-on attack on the person who is getting close to the truth, accusing them of all sorts of things.
And what about the McCanns? How many people have they lied to?