New separation anxiety in 4 year old

My just turned 4 year old daughter started school last September. She cried for the first 3 weeks or so then settled down well. The teacher is pleased with her progress and she seems to have lots of friends, gets invited to birthday parties and always has lots of kids saying goodbye to her when I go to pick her up. She has always been quite sociable, especially with children and appeared to be enjoying school.
At the end of April her father went abroad for 2 weeks, at a time which coincided with the school holidays. She didn't go with him as it was too long a trip and I felt she was too young to be away from me for so long.
When he returned she went back to school and ever since this time she cries not to go pretty much every morning, saying that she wants to stay with me (her mother). She apparently stops after I have left and joins in the activities etc. However, she has suddenly switched from a child who liked school to one who really dislikes it, although nothing has apparently happened to make this the case.
Is this just a normal phase at this age? How can I help her? Is it related to her father's trip away ? (He also took her younger half sister as she is not yet in school, so maybe it's jealousy ?). Any advice would be great as I hate leaving her like it.
She also cried a little last week when I left her at a friend's birthday party, but only 30 seconds or so and then she was fine, although she constantly wants to be cuddled, carried etc at the moment.
thanks

[jdtm]

I suspect the separation anxiety is not new; it is the circumstances which has exacerbated the anxiety.  Anxiety tends to be an inherited trait but a behaviour which one can learn to manage and cope.  With patience and nurturing but not over-compensating, I suspect she will be fine.  Also, at this time of year, children become so exhausted from learning and playing and interacting at school that they often appear to collapse in the form of tantrums and unruliness and tears.  I suspect she just needs a break.

It might be wise to read articles on the internet re school and anxiety in preparation for the next school year as usually there will be a setback at the beginning of the year (common with children and anxiety).  I might suggest you google phrases as "anxiety and school" or "kindergarten anxiety" or "separation anxiety in young children" or similar words/phrases.  There's lots of information on the internet and bookstores re this topic. It does appear that your child's anxiety is not severe.   All the best ...

[AnnieBrooke]

She was too young to be away from you for so long but her younger sister got to go with him because she was not yet in school?  I'd hate school, too, if it apparently deprived me of my dad.  I don't think it's jealousy of the sister, it's deprivation of parental time and attention.  I can always tell when my son is feeling like my husband and I are too distracted by our work to pay enough attention to him because he begins to dislike school.

[jdtm]

I suspect the separation anxiety is not new; it is the circumstances which has exacerbated the anxiety.  Anxiety tends to be an inherited trait but a behaviour which one can learn to manage and cope.  With patience and nurturing but not over-compensating, I suspect she will be fine.  Also, at this time of year, children become so exhausted from learning and playing and interacting at school that they often appear to collapse in the form of tantrums and unruliness and tears.  I suspect she just needs a break.

It might be wise to read articles on the internet re school and anxiety in preparation for the next school year as usually there will be a setback at the beginning of the year (common with children and anxiety).  I might suggest you google phrases as "anxiety and school" or "kindergarten anxiety" or "separation anxiety in young children" or similar words/phrases.  There's lots of information on the internet and bookstores re this topic. It does appear that your child's anxiety is not severe.   All the best ...